1. Field of the Invention
The present invention relates to an oil-water separator with self-priming pump and specifically relates to an oil-water separator for recovered oil resulting from recovery of scum in a sewage treatment plant, food factory, etc., coolant oil of a machining center, floating oil in a degreasing process in plating, etc.
2. Description of the Prior Arts
Conventionally, oil, for example, in industrial wastewater is ordinarily input in a diversely mixed state, and actual conditions of wastewater having oil and foreign matter mixed therein are totally non-uniform, being dependent on details of work performed from day to day, season, air temperature, water temperature, miscellaneous matter mixed in wastewater, etc.
However, there are problems in treating such wastewater in a terminal treatment plant in that costs of consumption power, etc., and large-scale equipment are required and, at the same time, environmental impact must be considered because large quantities of chemicals are used, etc.
Thus to resolve the conventional issues, the present inventor prior proposed an oil-water separator in which water and oil are first subject to rough separation by a cyclone portion, the water and the oil are thereafter subject to main separation by a specific gravity difference separation tank, and the water and the oil that could not be separated by the main separation are separated in a lower separation tank having a brush disposed in a spiral form to easily and rapidly perform separation of a mixed liquid with water and oil mixed therein by a simple and compact equipment that does not use any chemicals whatsoever and without worry of environmental pollution. Refer to Patent Document 1 (Japanese Published Unexamined Patent Application No. 2001-104705) and Patent Document 2 (Japanese Published Unexamined Patent Application No. 2001-321605).